--- /dev/null
+; RUN: opt -mtriple=amdgcn-- -S -structurizecfg -si-annotate-control-flow %s | FileCheck -check-prefix=OPT %s
+; RUN: llc -march=amdgcn -verify-machineinstrs < %s | FileCheck -check-prefix=GCN %s
+
+
+; OPT-LABEL: @annotate_unreachable_noloop(
+; OPT-NOT: call i1 @llvm.amdgcn.loop
+
+; GCN-LABEL: {{^}}annotate_unreachable_noloop:
+; GCN: s_cbranch_vccnz
+; GCN-NOT: s_endpgm
+; GCN: .Lfunc_end0
+define void @annotate_unreachable_noloop(<4 x float> addrspace(1)* noalias nocapture readonly %arg) #0 {
+bb:
+ %tmp = tail call i32 @llvm.amdgcn.workitem.id.x()
+ br label %bb1
+
+bb1: ; preds = %bb
+ %tmp2 = sext i32 %tmp to i64
+ %tmp3 = getelementptr inbounds <4 x float>, <4 x float> addrspace(1)* %arg, i64 %tmp2
+ %tmp4 = load <4 x float>, <4 x float> addrspace(1)* %tmp3, align 16
+ br i1 undef, label %bb5, label %bb3
+
+bb3: ; preds = %bb1
+ %tmp6 = extractelement <4 x float> %tmp4, i32 2
+ %tmp7 = fcmp olt float %tmp6, 0.000000e+00
+ br i1 %tmp7, label %bb4, label %bb5 ; crash goes away if these are swapped
+
+bb4: ; preds = %bb3
+ unreachable
+
+bb5: ; preds = %bb3, %bb1
+ unreachable
+}
+
+
+; OPT-LABEL: @annotate_ret_noloop(
+; OPT-NOT: call i1 @llvm.amdgcn.loop
+
+; GCN-LABEL: {{^}}annotate_ret_noloop:
+; GCN: s_and_b64 vcc
+; GCN: s_cbranch_vccnz
+; GCN: s_endpgm
+; GCN: .Lfunc_end1
+define void @annotate_ret_noloop(<4 x float> addrspace(1)* noalias nocapture readonly %arg) #0 {
+bb:
+ %tmp = tail call i32 @llvm.amdgcn.workitem.id.x()
+ br label %bb1
+
+bb1: ; preds = %bb
+ %tmp2 = sext i32 %tmp to i64
+ %tmp3 = getelementptr inbounds <4 x float>, <4 x float> addrspace(1)* %arg, i64 %tmp2
+ %tmp4 = load <4 x float>, <4 x float> addrspace(1)* %tmp3, align 16
+ br i1 undef, label %bb5, label %bb3
+
+bb3: ; preds = %bb1
+ %tmp6 = extractelement <4 x float> %tmp4, i32 2
+ %tmp7 = fcmp olt float %tmp6, 0.000000e+00
+ br i1 %tmp7, label %bb4, label %bb5 ; crash goes away if these are swapped
+
+bb4: ; preds = %bb3
+ ret void
+
+bb5: ; preds = %bb3, %bb1
+ ret void
+}
+
+
+declare i32 @llvm.amdgcn.workitem.id.x() #1
+
+attributes #0 = { nounwind }
+attributes #1 = { nounwind readnone }